Coated abrasives



Sept. 5, 1967 I 3,339,320

W. E. CHRISTIAN COATED ABRASIVES Filed March 10; 1965 l VENTOR WA EE/v E. HRISTIAN ATTORNEY United States Patent 3,339,320 COATED ABRASIVES Warren E. Christian, Troy, N.Y., assignor to Norton Company, Troy, N.Y., a corporation of Massachusetts Filed Mar. 10, 1965, Ser. No. 438,563 2 Claims. (Cl. 51-399) ABSTRACT OF THE DISCLOSURE A coated abrasive cone having an internal adhesivelysecured locking tab adapted to retain the conical shape during grinding operations.

The present invention relates generally to coated abrasive devices and more specifically to small coated abrasive cones.

It has been common practice in industry to utilize coated abrasives in many forms and shapes for abrading purposes. One of the most popular forms has been a cone-shaped abrasive device formed by folding upon itself a disc of coated abrasive from which a segment has been cut and then adhering the edges of the resultant cone to each other or sometimes to an interliner.

Conventional methods for making such cones have proven satisfactory for cones over one inch or so in height and/ or diameter, but the cost of assembly of cones smaller than this has tended to restrict the usage of such small abrasive cones.

A principal object of the invention is the provision of a coated abrasive cone which is more firmly locked into conical shape than is a conventional cone.

Additional objects, if not specifically set forth herein, will be readily apparent to one skilled in the art from the following detailed description of the invention:

In the drawings:

FIGURE 1 is a plan view of the development of the cone of the present invention, showing an abrasive blank in the shape of such development.

FIGURE 2 illustrates the partial formation of the cone of the present invention from the abrasive blank shown in FIGURE 1.

FIGURE 3 illustrates the final formation of the cone from the partially complete cone of FIGURE 2.

Generally, the present invention relates to the provision of a locking tab which cooperates with the conical sides of an abrasive cone to firmly and efiectively lock such sides in the proper relationship to one another and to retain the cone in its proper shape and configuration during subsequent grinding operations which utilize such cone as the abrading medium.

More specifically, and referring now to FIGURE 1 of the drawings, reference numeral 10 identifies a blank of coated abrasive material, abrasive side down, which has been died out in the proper shape to form the cone of the present invention. The main body 11 of the blank 10 is in the shape of a circular disc from which has been cut a substantial segment of about 120 of arc. The main body 11 of the blank is hence defined by the are 12 (continued in dotted lines at 12') and radii 13-13. Extending from one side of the main body 11 and formed integrally therewith is a locking tab 14. This tab is immediately adjacent either end of the interrupted arc of the main body 11 and the base 12 of such tab 14 (shown as ice a dotted line) will extend through about 15 to 45 of are on the main body 11. The actual configuration of the extension forming tab 14 may vary as desired but should generally conform to the interior of the cone when it is subsequently folded over as described below. The preferred shape is shown in the embodiment illustrated in FIGURE 1.

Referring now to FIGURE 2, the radii 13-13 forming the interrupted arc portion of the main body 11 of blank 10 are brought together in edge-to-edge relationship to form a cone-shaped device 15 with the abrasive side 16 on the exterior of the cone 15. This is preferably done by inserting the blank, abrasive side down, in a form, schematically illustrated at 17. This form 17 has a tapered configuration corresponding to the shape of the cone to be produced and permits the edges 13 of the blank to be butted neatly and tightly against one another as shown in FIGURE 2. The tab 14 now extends up from the base 12 of cone 15 and-is to be folded over into the interior 15' of cone 15 with the fold being along the dotted line 12 which, as shown in FIGURE 1, forms the base of tab 14. Tab 14 may, in the case of a coarse grit abrasive, be skived in conventional fashion to remove the abrasive coating on the outer surface of the tab to provide a reduction in thickness if desired. A coating of adhesive 18 is applied to the non-abrasive side of tab 14 or in the alternative to the area of the inside 15' of cone 15 adjacent the meeting line of edges 13-13. In some instances it will be desirable to adhesive-coat both of these locations although usually one or the other is sufiicient.

As shown in FIGURE 3, tab 14 is folded over into cone 15 and covers the intersection of edges 13-13. The adhesive coating 18 on the non-abrasive side of tab 14 adheres the tab to the inside 15' of cone 15 and securely holds the butted edges 13-13 together.

This cone and the method of making as described herein is eflicient and is a definite advance over conventional cone-making operations in the abrasive field. The coated abrasive material used may be any of the known constructions such as paper or cloth-backed abrasive materials and the abrasive grit and bond may vary as necessary to produce the desired abrasive properties. The type of adhesive used to hold the locking tab in place is not critical and any glue or resin adhesive or the like may be used as desired.

Obviously, many modifications and variations may be made without departing from the spirit of the invention above-described and, therefore, only such limitations should be imposed on the scope of the invention as are contained in the appended claims.

I claim:

1. In a coated abrasive cone formed from a conical piece of coated abrasive material with the abrasive surface thereof on the outside of the cone and the edges of the material forming said cone butted one against the other, the improvement which comprises: a locking tab formed from and integral with the coated abrasive material forming said conical piece, said locking tab being folded over into the interior of said cone to cover said butted edges and being adhesively secured to the interior of said cone to hold said edges in position.

2. A coated abrasive cone as in claim 1 wherein said locking tab has been skived to remove the abrasive coating therefrom.

(References on following page) References Cited UNITED STATES PATENTS Teague 51-407 Sharon 229-45 Iacoponelli 51-394 X Barbieri 229-15 Fenton 51-396 4 2,456,912 12/1948 Burrows 229-45 X 3,092,937 6/ 1963 Tocci-Guilbert 51-197 FOREIGN PATENTS 19,156 5/1935 Australia.

ROBERT C. RIORDON, Primary Examiner.

D. G. KELLY, Assistant Examiner. 

1. IN A COATED ABRASIVE CONE FORMED FROM A CONICAL PIECE OF COATED ABRASIVE MATERIAL WITH THE ABRASIVE SURFACE THEREOF ON THE OUTSIDE OF THE CONE AND THE EDGES OF THE MATERIAL FORMING SAID CONE BUTTED ONE AGAINST THE OTHER, THE IMPROVEMENT WHICH COMPRISES: A LOCKING TAB FORMED FROM AND INTEGAL WITH THE COATED ABRASIVE MATERIAL FORMING SAID CONICAL PIECE, SAID LOCKING TAB BEING FOLDED OVER INTO THE INTERIOR OF SAID CONE TO COVER SAID BUTTED EDGES AND BEING ADHESIVELY SECURED TO THE INTERIOR OF SAID CONE TO HOLD SAID EDGES IN POSITION. 